In humans, the
gastrocnemius ( or )
muscle is a very powerful superficial
muscleMuscle is the contractile tissue of the body and is derived from the mesodermal layer of embryonic germ cells. Muscle cells contain contractile filaments that move past each other and change the size of the cell. They are classified as skeletal, cardiac, or smooth muscles. Their function is to...
that is in the back part of the lower leg and also called the calf. It runs from its two heads just above the
kneeThe knee joint joins the thigh with the leg and consists of two articulations: one between the femur and tibia, and one between the femur and patella. It is the largest and most complicated joint in the human body. The knee is a mobile trocho-ginglymus , which permits flexion and extension as well...
to the
heelThe heel is the prominence at the posterior end of the foot. It is based on the projection of one bone, the calcaneus, behind the articulation of the bones of the lower leg. In the long-footed mammals, both the hoofed species and the clawed forms which walk on the toes , the heel is well above the...
, and is involved in standing, walking, running and jumping. Along with the
soleus muscleIn humans and some other mammals, the soleus is a powerful muscle in the back part of the lower leg . It runs from just below the knee to the heel, and is involved in standing and walking. It is closely connected to the gastrocnemius muscle and some anatomists consider them to be a single muscle,...
it forms the calf muscle. Its function is planter flexing the foot at the ankle joint. In a 1967 EMG study, Herman and Bragin concluded that its most important role was planter flexing in large contractions and in rapid development of tension.
The gastrocnemius is located with the soleus in the posterior (back) compartment of the leg.
In humans, the
gastrocnemius ( or )
muscle is a very powerful superficial
muscleMuscle is the contractile tissue of the body and is derived from the mesodermal layer of embryonic germ cells. Muscle cells contain contractile filaments that move past each other and change the size of the cell. They are classified as skeletal, cardiac, or smooth muscles. Their function is to...
that is in the back part of the lower leg and also called the calf. It runs from its two heads just above the
kneeThe knee joint joins the thigh with the leg and consists of two articulations: one between the femur and tibia, and one between the femur and patella. It is the largest and most complicated joint in the human body. The knee is a mobile trocho-ginglymus , which permits flexion and extension as well...
to the
heelThe heel is the prominence at the posterior end of the foot. It is based on the projection of one bone, the calcaneus, behind the articulation of the bones of the lower leg. In the long-footed mammals, both the hoofed species and the clawed forms which walk on the toes , the heel is well above the...
, and is involved in standing, walking, running and jumping. Along with the
soleus muscleIn humans and some other mammals, the soleus is a powerful muscle in the back part of the lower leg . It runs from just below the knee to the heel, and is involved in standing and walking. It is closely connected to the gastrocnemius muscle and some anatomists consider them to be a single muscle,...
it forms the calf muscle. Its function is planter flexing the foot at the ankle joint. In a 1967 EMG study, Herman and Bragin concluded that its most important role was planter flexing in large contractions and in rapid development of tension.
Anatomy
The gastrocnemius is located with the soleus in the posterior (back) compartment of the leg. It originates from the posterior (back) surfaces of the distal head of the
femurThe femur, or thigh bone, is the most proximal bone of the leg in vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs...
. Its other end forms a common tendon with the
soleus muscleIn humans and some other mammals, the soleus is a powerful muscle in the back part of the lower leg . It runs from just below the knee to the heel, and is involved in standing and walking. It is closely connected to the gastrocnemius muscle and some anatomists consider them to be a single muscle,...
; this tendon is known as the calcaneal tendon or
Achilles TendonThe Achilles tendon , also known as the calcaneal tendon or the tendo calcaneus, is a tendon of the posterior leg. It serves to attach the gastrocnemius and soleus muscles to the calcaneus bone.-Anatomy:The Achilles is the tendonous extension of three muscles in the lower leg: gastrocnemius,...
and inserts onto the posterior surface of the
calcaneusIn humans, the calcaneus or heel bone is a bone of the tarsus of the foot which constitute the heel. In some other animals, it is the point of the hock.- Human anatomy :...
, or mountain bone.
Deep to the gastrocnemius (farther from the skin) is the soleus muscle. Some anatomists consider both to be a single muscle, the
triceps suraeThe triceps surae is a pair of muscles located at the calf - the gastrocnemius and the soleus. These muscles both insert into the calcaneus, the bone of the heel of the human foot, and form the major part of the muscle of the back part of the lower leg, commonly known as the calf muscle.The...
. The plantaris muscle and a portion of its tendon run between the two muscles, which is involved in "locking" the knee from the standing and
posterior tibial veinIn anatomy, the posterior tibial vein of the lower limb carries blood from the posterior compartment and plantar surface of the foot to the popliteal vein which it forms when it joins with the anterior tibial vein....
and the tibial nerve. Since the anterior compartment of the leg is lateral to the tibia, the bulge of muscle medial to the
tibiaThe tibia, shinbone, or shankbone is the larger and stronger of the two bones in the leg below the knee in vertebrates and connects the knee with the ankle bones.The tibia is named for the greek aulos flute, also known as a tibia.-In humans:...
on the anterior side is actually the posterior compartment. The soleus is superficial midshaft of the tibia.
Frequently there is a
sesamoid boneIn anatomy, a sesamoid bone is a bone embedded within a tendon.Sesamoid bones are found in locations where a tendon passes over a joint, such as the hand, knee, and foot. Functionally, they act to protect the tendon and to increase its mechanical effect...
called the "
fabellaThe fabella is a small sesamoid bone found in some mammals embedded in the tendon of the lateral head of the gastrocnemius muscle behind the lateral condyle of the femur. It is a variant of normal anatomy and present in humans in 10% to 30% of individuals. Rarely, there are 2 or 3 of these bones...
" in the lateral head of gastrocnemius muscle.
Clinical significance
The gastrocnemius muscle is very prone to spasms; the painful, involuntary, contraction of the muscle for up to several minutes.
http://www.webmd.com/a-to-z-guides/nighttime-leg-cramps-topic-overview
This muscle is prone to injury called torn calf muscle which is disabling.
The Gastrocnemius muscle may also become inflamed due to overuse.
Anti-inflammatoryAnti-inflammatory refers to the property of a substance or treatment that reduces inflammation. Anti-inflammatory drugs make up about half of analgesics, remedying pain by reducing inflammation as opposed to opioids which affect the brain.-Medications:...
and physical therapy may be necessary.
Anatomical abnormalities involving the medial head of gastrocnemius muscle results in popliteal entrapment syndrome
External links
- WebMD Nighttime Leg Cramps: http://www.webmd.com/a-to-z-guides/nighttime-leg-cramps-topic-overview